Ice shield



. Feb. 26, 1957 E. J. FIELD ICE-SHIELD Filed Sept. 10. 1955 I INVENTOR. R677 J. 7/510 United States Patent ICE SHIELD Everett J. Field, Jeannette, Pa., assignor to I-T-E Circuit Breaker Company, Philadelphia, Pa.

Application September 10, 1953, Serial No. 379,455

1 Claim. (Cl. 286-7) My invention relates to ice shields and is more particularly directed to a novel arrangement which will minimize the operating torque required to break loose a shaft of glazed ice at a bearing.

Outdoor installations of disconnect switches frequently require vertically rotating operating means so that the switch can be operated from a remote point such as the ground. In order to prevent excessive whipping ,or movement of the main operating or control rod, it is necessary to provide guide plates to act as intermediate bearing plates between the rod extremities.

In areas where weather conditions cause formations of glazed ice, considerable resistance to operation results due to the ice formation at the bearing guide plates. In many installations, an ice thickness in excess of one inch is common due to the fact that the guide plate provides a horizontal surface on which the water gathers.

The main reason for the extra build up of ice thickness on the guide plates is the fact that the rain striking the vertical operating rod runs down the rod until it meets an obstacle which in this case is the bearing guide plate. Thus, the rain water, slowed up by the guide plate, freezes before travelling further. Hence, the thickness of ice that would normally form on the guide plate as a result of rain striking the member directly is augmented by the water which runs vertically down the operating rod to the bearing plate. This undesirable construction wherein large thicknesses of ice deposits are formed on parts having relative movement has created serious obstacles and has resulted in unsuccessful operation of disconnect switches. That is, since the successful operation of the disconnect switch by means of the operating rod requires that a large thickness of ice must be sheared before the shaft can be rotated, unsuccessful operation frequently results.

With my novel invention, I have overcome the obstacles of the prior art arrangement by eliminating or minimizing the volume of ice which is formed at the shear line boundary.

Observation of tests and installed equipment indicate that no appreciable ice is formed on the vertical surfaces. That is, that for a vertical cylindrical surface, a cross section taken perpendicular to the axis of the cylinder will include a cross-sectional area of ice that is only a small percentage of the cross-sectional area of ice that will be developed under the same conditions around the same cylinder at a point where a horizontal plane surface impedes the downward flow of water.

Recognizing the results of the above noted analysis, I have devised a novel ice shield wherein the horizontal plane surface, which is formed by the bearing plates, is removed from the shear line boundary so that thick ice formations will not have to be sheared when an attempt is made to rotate the operating shaft.

I have achieved this result by providing a vertical hollow cylindrical section permanently secured and extending upwardly from the bearing plate. A second cylindrical member mounted on and concentric to the operating shaft serves as a partial housing for the first mentioned stationary hollow cylinder. Thus, the water flowing down the operating shaft will impede upon the partial housing secured to the shaft and thus be guided to the corner existing at the attachment point between the stationary hollow cylinder and the horizontal plane surface of the bearing plate. Thus, thick ice will be formed in the corner area in which the parts have no relative movement to each other.

Since the partial housing diverts the water from the apparatus having relative movement, the ice formations will always be located at an area which will not impede the operation of the main operating shaft.

Accordingly, a primary object of my invention is to provide a novel ice shield for vertical rotating members which require bearing plates to insure that no thick ice will be formed at an area in which the parts have relative movement. 7

Another object of my invention is to provide a movable and stationary member for a vertical operating shaft wherein the movable member serves to divert water away from the stationary member so that ice will be formed in an area which will not impede the operation of the vertical shaft.

These and other objects of my invention will be apparent from the description when taken in connection with the drawings in which:

Figure 1 is a cross-sectional view of a vertical operating shaft for a disconnect switch and illustrates my novel ice shield in relation thereto.

Figure 2 is a cross-sectional view of a vertical operating shaft for outdoorequipment and illustrates a modified version of my novel ice shield adapted thereto.

The operating shaft 10 is rotatable about its axis 11 and is controlled from some remote point, as for example near the ground, to thereby operate electrical equipment which is secured to its upper end.

Due to the length of the operating shaft 10, it is necessary to provide a standard guide plate 12 having guide plate bushing or bearing 13. The novel ice shield of my invention is designed to protect the vertical operating rod 10 and provide means whereby the large volume of ice which will be formed on the horizontal surface of the guide plate 12 will not interfere with the proper rotational operation of the rod or shaft 10.

A hollow cylindrical member 14 is permanently mounted by the weld 15 or other suitable fastening means on the upper surface of the guide plate 12. The hollow cylindrical member 14 may be mounted substantially concentric with the main operating shaft 10 and serves as a stationary member on my novel ice shield. The inside diameter of the stationary member 14 is slightly larger than the outside diameter of the vertical operating rod 10 and the relative dimensions are not critical.

The upper portion 17 of the stationary member 14 is preferably a sector of a cone with its axis coinciding with axis 11 and the vertical operating rod 10.

'It will be'not-ed that stationary member 14 may have a turned down top section which is turned Within a counter-bored section of rotation member 16. That is, the configuration of surfaces 17, 19 must prevent entrance of water into the cavity during a period of rain that precedes a freezing temperature and hence, may be shaped as illustrated or any other contour which will achieve this object.

The second main portion of my novel ice shield is the annular piece 16 which can be adjustably mounted substantially concentric along the operating rod 10 and clamped at any desirable position thereon by any desirable means as for example by means of set screw 18.

apsaoee 3. The adjustable piece 16 is clamped on the operating rod immediately above the stationary member 14 and displaced therefrom a distance to assure a clearance between the facing surfaces 17 and 19. This clearance 17-19 between the movable member 16 and the stationary member 14 must be sufficiently large to allow for a range of lateral motion of the operating rod 10 permitted by the clearance of the guide plate bushing 13. This boundary or clearance space 17,-19 between'the rotating and stationary members 14-16 is located sufiiciently far above the horizontal surface 22 of the guide plate 12 to always clear the horizontal build up of ice, for example three inches.

Also, the lateral thrust load of, the vertical operating rod 10 will be taken up by the guide plate bushing 13 so that there need be no bearing between thestationary and movable members 14-16. Hence, there will be no introduction of friction resistance due to the fact that ice shield members 14-16 have relative movement with respect to each other. It will also be noted that the apex of the cone, including the surfaces 17 and 19, is above the clearance space 17-19 to preclude the entrance of moisture through the clearance space.

It will be noted that therotating member 16 of the ice shield may be provided with a Water-proof seal 21) which can be sandwiched between the shield 16. and the rod 10. i

it will also be noted that the inside contour 19 on the under side of the rotating member 16 corresponds to the conical contour 17 at the upper end of, the stationary member 14. The purpose of this construction is to prevent the entrance of water into the internal part of the ice shield 14-46.

Hence, with the arrangement illustrated in Figure 1, I have provided a device that has a true vertical surface both above and below the boundaryline 17-19 existing between the stationary and rotating members 14-16. The boundary line 17-19 is located at a sufficient distance above the horizontal surface 22 of the guide plate 12 to assure that it will always be above the layer of ice that buildsup on the guide plate 12.

Hence, the cross-section of. ice that will be placed in shear will be reduced to an absolute minimum and therefore interferences to proper operation of the operating rod 10" caused by ice formation will be eliminated.

Thus, with my novel arrangement, anadaption of a stationary and movable ice shield can be applied to a standard operating shaft and guide plate to insure that there will be no ice formations at a boundary area between relatively movable parts.

In Figure 2, I have shown a simplified and modified version of my novel ice shield. As heretofore noted'in Figure 1, the main operating shaft 10 rotates about its axis 11 and is provided with a stationary guide plate 12 having a guide plate bushing 13; a hollow cylindrical member 14'is secured to the guide plate 12 at the weld or by any other suitable attaching means.

Except for the upper conical surface 17, notedin connection with Figure l, the stationary member 14' of. the modified view of Figure 2 is similar in construction to member 14 set forth and described in Figure 1. However, in the modified view of Figure 2, the rotating mem ber 16' of the ice shield is a cup shaped housing mounted on and concentric'to operating shaft or rod 10. The

4 rotating member 16 may be welded or adjustably secured to the operating shaft 10.. in any desirable manner.

By providing the arrangement of Figure 2, the clearance distance 25 between the rotating member 16' and a stationary member 14' is not critical.

When the modified ice shield arrangement of Figure 2 is subjected to rain storm conditions, the water will follow the path generally indicated-by arrows 26. That is, the water will flow from the upper vertical surface of the operating rod 10, over the" outside of the rotating member or housing 16' to the horizontal surface 22 of the bearing plate 12.

Hence all of the ice formed from this water will be located at an arearemote from surfaces having relative movement.

In the foregoing, I have described my invention only in connection with preferred embodiments thereof. Many variations and modifications of the principles of my invention within the scope of the description herein are obvious. Accordingly, I prefer to be bound not by the specific disclosure herein but only by the appending claim. l

I claim:

An ice shield, for a verticallymounted rotatable operating shaft; a horizontal bearing guide plate positioned concentric to said operating shaft and extending perpendicular to the axis of said operating shaft; a hollow stationary member being, rigidly secured at its lower end to the upper horizontal surface of said guide plateand mounted substantially concentric with respect to said shaft; said stationary memberhaving an internal 'diameter larger than the external diameter ofsaid shaft; s aid shaft being positioned withinv said stationary member and extending above the upper end of said stationary member and belowthe lower horizontal surface of said guide plate; said shaft being rotatablymounted with re spect to said guide plate; a shield mounted on said op erating shaft above the upper end of said stationary member and substantially concentric. with 'said shaft; said shield. having an inside diameter substantially equal to the outsidediameter of said, shaft; said, shield having an outside diameter at least equal tothc outside diameter of said. stationary member; a portion of said shield overlapping a portion of said stationary member and being concentric therewith; said shield having an upper surface that is flared away from said shaft toward said guide plate to guidefluid to the upper, horizontal surface of said guide plate when said shield'is stationaryto thereby prevent ice formation at areas adjacent torelatively movable parts; the lower edge of said shield, and the upper end of said stationary member being atv a height that exceeds any expected build-up of ice on said upper horizontal surface of said guide plate.

References Cited in the file of this patent UNITED STATES PATENTS 1,574,211 Taylor Feb. 23, 1926 1,806,748 Edwards May 26, 1931 1,888,475 Schmitz Nov. 22, 1932 1,999,662 Nell Apr. 30, 1935 2,313,308 Allen Mar. 9, 1943 2,377,770 Fish et al. June 5, 1945 

